Solution theory model for thermophysical properties of refrigerant/lubricant mixtures

ABSTRACT: A general model for predicting the thermos physical properties of refrigerant/lubricant mixtures has been developed based on applicable theory for the excess Gibbs energy of non-ideal solutions. In our approach, flexible thermodynamic forms are chosen to describe the properties of both the...

Full description

Autores:
Restrepo Cossio, Albeiro Alonso
Bent, Gary
Michels, Harvey
Tipo de recurso:
Article of investigation
Fecha de publicación:
2009
Institución:
Universidad de Antioquia
Repositorio:
Repositorio UdeA
Idioma:
eng
OAI Identifier:
oai:bibliotecadigital.udea.edu.co:10495/26740
Acceso en línea:
http://hdl.handle.net/10495/26740
Palabra clave:
Refrigerants
Refrigerantes
Solubility
Solubilidad
Enthalpy
Entalpía
Entropy
Entropía
Density
Densidad
http://aims.fao.org/aos/agrovoc/c_2186
Thermophysical propertie
Polyolester
Alkylbenzen
Non-ideal solution
Heat capacity
http://aims.fao.org/aos/agrovoc/c_28326
http://aims.fao.org/aos/agrovoc/c_7233
http://aims.fao.org/aos/agrovoc/c_641424d2
http://aims.fao.org/aos/agrovoc/c_1fc62594
Rights
openAccess
License
http://creativecommons.org/licenses/by-nc-nd/2.5/co/
Description
Summary:ABSTRACT: A general model for predicting the thermos physical properties of refrigerant/lubricant mixtures has been developed based on applicable theory for the excess Gibbs energy of non-ideal solutions. In our approach, flexible thermodynamic forms are chosen to describe the properties of both the gas and liquid phases of refrigerant/lubricant mixtures. After an extensive study of models for describing non ideal liquid effects, the Wohl [3]-suffix equations, which have been extensively used in the analysis of hydro-carbon mixtures, have been developed into a general form applicable to mixtures where one component is a polyolester or alkylbenzene lubricant. We have developed anon ideal solution computer code, based on the Wohl model that predicts dew point orbubble point conditions over a wide range of composition and temperature and includes the calculation of the enthalpy and entropy of refrigerant/lubricant mixtures. Our present analysis includes the thermodynamic properties of an ideal solution mixture and the corrections due to non-ideal solution behavior. These non-ideal solution corrections are based on analysis of the excess Gibbs energy of the mixture. We find that these non-ideal solution corrections are small (\4%) for most refrigerant/lubricant mixtures, except at very low temperatures.